I have a PI coil that is 48” x 48”. It will go very deep on big metal objects. Through the air 35’ on a car. 25’ on a metal garbage can. Air on a beer can 8’. In saltwater about 12’. When I use it in the water I tow it about 12’ plus off the bottom, just to not get beer cans. It will not find tiny coins and pull tabs. If I take the coil and fold it over to be a half sized coil about 36” x 36” it still will go very deep and still will not find tiny things. If I fold it again to a 24” x 25” it will find tiny things, maybe not a gold alloy ring because it is not hot on that, too slow of a pulse. But it will go pretty deep on a big object. Just a 10” Pulse coil will go 5’- 6’ on a big iron object like a 24” iron anchor. I have dug that, and find gold alloy rings. I would assume a 10’ x 10’ coil would still pick up beer cans at any depth. Maybe if you can slow the pulse rate it will eliminate small stuff. I will try that and get back to you. It will still pick up beer cans (my detector) on as slow a pulse as I can go. Maybe not as deep? I will try that out. My big PI has automatic SAT self adjusting threshold, which helps when going over different types of soil, it does not have to be ground balanced. That will also allow you to have metal inside the coils detection range and it will quit sounding off, but it will be slightly less sensitive. It is like ground balancing with a target under the coil. So if you had a PI that has auto SAT, you could have a couple beer cans near the coil making it less sensitive. It would eliminate some tiny trash. Possibly could have enough cans in the zone to eliminate beer cans. I never tried that though as I would be counter productive, but could eliminate beer cans would help you. I will try that. And let you know.
?? any infor would be helpful
